Generation of high-yield insulin producing cells from human-induced pluripotent stem cells on polyethersulfone nanofibrous scaffold

Research progress of autoimmune diseases based on induced pluripotent stem cells

Autoimmune diseases can damage specific or multiple organs and tissues, influence the quality of life, and even cause disability and death. A 'disease in a dish' can be developed based on patients-derived induced pluripotent stem cells (iPSCs) and iPSCs-derived disease-relevant cell types to provide a platform for pathogenesis research, phenotypical assays, cell therapy, and drug discovery. With rapid progress in molecular biology research methods including genome-sequencing technology, epigenetic analysis, '-omics' analysis and organoid technology, large amount of data represents an opportunity to help in gaining an in-depth understanding of pathological mechanisms and developing novel therapeutic strategies for these diseases. This paper aimed to review the iPSCs-based research on phenotype confirmation, mechanism exploration, drug discovery, and cell therapy for autoimmune diseases, especially multiple sclerosis, inflammatory bowel disease, and type 1 diabetes using iPSCs and iPSCs-derived cells.

Polyethersulfone Polymer for Biomedical Applications and Biotechnology

Polymers stand out as promising materials extensively employed in biomedicine and biotechnology. Their versatile applications owe much to the field of tissue engineering, which seamlessly integrates materials engineering with medical science. In medicine, biomaterials serve as prototypes for organ development and as implants or scaffolds to facilitate body regeneration. With the growing demand for innovative solutions, synthetic and hybrid polymer materials, such as polyethersulfone, are gaining traction. This article offers a concise characterization of polyethersulfone followed by an exploration of its diverse applications in medical and biotechnological realms. It concludes by summarizing the significant roles of polyethersulfone in advancing both medicine and biotechnology, as outlined in the accompanying table.

Generation of glucose sensitive insulin-secreting cells from human induced pluripotent stem cells on optimized polyethersulfone hybrid nanofibrous scaffold

BACKGROUND

In the realm of diabetes treatment, various strategies have been tried, including islet transplantation and common drug therapies, but the limitations of these procedures and lack of responsive to the high number of patients have prompted researchers to develop a new method. In recent decades, the use of stem cells and three-dimonsional (3D) scaffold to produce insulin-secreting cells is one of the most promising new approaches. Meanwhile, human-induced pluripotent stem cells (iPSCs) propose due to advantages such as autologousness and high pluripotency in cell therapy. This study aimed to evaluate the differentiation of iPSCs into pancreatic islet insuli-producing cells (IPCs) on Silk/PES (polyethersulfone) nanofibers as a 3D scaffold and compare it with a two-dimonsional (2D) cultured group.

METHODS

Investigating the functional, morphological, molecular, and cellular characteristics of differentiated iPSCs on control cultures (without differentiation medium), 2D and 3D were measured by various methods such as electron microscopy, Q-PCR, immunofluorescence, western blot, and ELISA.

RESULTS

This investigation revealed that differentiated cells on the 3D Silk/PES scaffold expressed pancreatic specific-markers such as insulin and pdx1 at higher levels than the control and 2D groups, with a significant difference between the two groups. All results of Q-PCR, immunocytochemistry, and western blot showed that IPCs in the silk/PES 3D group was more efficient than in the 2D group. In the face of these cases, the release of insulin and C-peptide in response to several concentrations of glucose in the 3D group was significantly higher than in the 2D culture.

CONCLUSION

Finally, our findings displayed that optimized Silk/PES 3D scaffolds can enhance the differentiation of IPCs from iPSCs compared to the 2D culture group.

Tissue engineering approaches and generation of insulin-producing cells to treat type 1 diabetes

Tissue engineering (TE) has become a new effective solution to a variety of medical problems, including diabetes. Mesenchymal stem cells (MSCs), which have the ability to differentiate into endodermal and mesodermal cells, appear to be appropriate for this function. The purpose of this review was to evaluate the outcomes of various researches on the insulin-producing cells (IPCs) generation from MSCs with TE approaches to increase efficacy of type 1 diabetes treatments. The search was performed in PubMed/Medline, Scopus and Embase databases until 2021. Studies revealed that MSCs could also differentiate into IPCs under certain conditions. Therefore, a wide range of protocols have been used for this differentiation, but their effectiveness is very different. Scaffolds can provide a microenvironment that enhances the MSCs to IPCs differentiation, improves their metabolic activity and up-regulate pancreatic-specific transcription factors. They also preserve IPCs architecture and enhance insulin production as well as protect against cell death. This systematic review offers a framework for prospective research based on data. In vitro and in vivo evidence suggests that scaffold-based TE can improve the viability and function of IPCs.

Nanofiber-based systems intended for diabetes

Diabetic mellitus (DM) is the most communal metabolic disease resulting from a defect in insulin secretion, causing hyperglycemia by promoting the progressive destruction of pancreatic β cells. This autoimmune disease causes many severe disorders leading to organ failure, lower extremity amputations, and ultimately death. Modern delivery systems e.g., nanofiber (NF)-based systems fabricated by natural and synthetic or both materials to deliver therapeutics agents and cells, could be the harbinger of a new era to obviate DM complications. Such delivery systems can effectively deliver macromolecules (insulin) and small molecules. Besides, NF scaffolds can provide an ideal microenvironment to cell therapy for pancreatic β cell transplantation and pancreatic tissue engineering. Numerous studies indicated the potential usage of therapeutics/cells-incorporated NF mats to proliferate/regenerate/remodeling the structural and functional properties of diabetic skin ulcers. Thus, we intended to discuss the aforementioned features of the NF system for DM complications in detail.

Comparing the Therapeutic Potential of Stem Cells and their Secretory Products in Regenerative Medicine

Cell therapy involves the transplantation of human cells to replace or repair the damaged tissues and modulate the mechanisms underlying disease initiation and progression in the body. Nowadays, many different types of cell-based therapy are developed and used to treat a variety of diseases. In the past decade, cell-free therapy has emerged as a novel approach in regenerative medicine after the discovery that the transplanted cells exerted their therapeutic effect mainly through the secretion of paracrine factors. More and more evidence showed that stem cell-derived secretome, i.e., growth factors, cytokines, and extracellular vesicles, can repair the injured tissues as effectively as the cells. This finding has spurred a new idea to employ secretome in regenerative medicine. Despite that, will cell-free therapy slowly replace cell therapy in the future? Or are these two modes of treatment still needed to address different diseases and conditions? This review provides an indepth discussion about the values of stem cells and secretome in regenerative medicine. In addition, the safety, efficacy, advantages, and disadvantages of using these two modes of treatment in regenerative medicine are also critically reviewed.

Decellularized Matrix Bioscaffolds: Implementation of Native Microenvironment in Pancreatic Tissue Engineering

ABSTRACT

Type 1 diabetes is an autoimmune disease, and its incidence is usually estimated in the range of 5% to 10%. Currently, the administration of exogenous insulin is the standard of care therapy. However, this therapy is not effective in some patients who may develop some chronic complications. Islet transplantation into the liver is another therapy with promising outcomes; however, the long-term efficacy of this therapeutic option is limited to a small number of patients. Because native extracellular matrix (ECM) components provide a suitable microenvironment for islet functions, engineering a 3-dimensional construct that recapitulates the native pancreatic environment could address these obstacles. Many attempts have been conducted to mimic an in vivo microenvironment to increase the survival of islets or islet-like clusters. With the advent of decellularization technology, it is possible to use a native ECM in organ engineering. Pancreatic decellularized bioscaffold provides proper cell-cell and cell-ECM interactions and retains growth factors that are critical in the determination of cell fate within a native organ. This review summarizes the current knowledge of decellularized matrix technology and addresses its possible limitations before use in the clinic.

Pancreatic Extracellular Matrix/Alginate Hydrogels Provide a Supportive Microenvironment for Insulin-Producing Cells

Type 1 diabetes mellitus (T1DM), as an autoimmune deficiency disease, is associated with an absolute deficiency of insulin subject to islet β-cell destruction. Insulin-producing cells (IPCs) differentiated from induced pluripotent stem cells are an ideal replacement origin of β-cells, which can be applied for cell transplantation therapies in T1DM. At present, more strategies focus on inducing and differentiating to obtain IPCs; however, the unsatisfactory differentiation efficiency and the lack of ideal carriers for in vivo transplantation limited their application. It is necessary to consider the cell microenvironment by constructing a biomimetic niche to improve the differentiation and transplantation efficiency. The main components of the extracellular matrix derived from pancreatic (the niche of β-cells) decellularization were retained, which could provide the ideal extracellular microenvironment for IPCs. In this research, a hydrogel prepared with alginate (Alg) and the pancreatic extracellular matrix (pECM) was assessed for the beneficial outcomes on encapsulated IPCs. The results showed that pECM/Alg improved the differentiation efficiency and promoted insulin secretion and the expression of insulin-related genes as well. Besides, pECM/Alg-encapsulated IPCs exhibited obvious biocompatibility in vivo, which can prolong the transplantation effect and hypoglycemic function by reducing the inflammatory reaction. RNA-seq indicated that the PI3K/Akt pathway may be related to the improvement of the differentiation efficiency and function of IPCs. In general, the pECM/Alg hydrogel provides an ideal biomimetic microenvironment for IPCs and is suitable for in vivo transplantation.

Stem Cell-Derived Insulin-Producing Cells in 3D Engineered Tissue in a Perfusion Flow Bioreactor

To circumvent the lack of donor pancreas, insulin-producing cells (IPCs) derived from pluripotent stem cells emerged as a viable cell source for the treatment of type 1 diabetes. While it has been shown that IPCs can be derived from pluripotent stem cells using various protocols, the long-term viability and functional stability of IPCs in vitro remains a challenge. Thus, the principles of three-dimensional (3D) tissue engineering and a perfusion flow bioreactor were used in this study to establish 3D microenvironment suitable for long-term in vitro culture of IPCs-derived from mouse embryonic stem cells. It was observed that in static 3D culture of IPCs, the viability decreased gradually with longer time in culture. However, when a low flow (0.02 mL/min) was continuously applied to 3D IPC containing tissues, enhanced survival and function of IPCs were demonstrated. IPCs cultured under low flow exhibited a significantly enhanced glucose responsiveness and upregulation of Ins1 compared to that of static culture. In summary, this study demonstrates the feasibility and benefits of 3D engineered tissue environment combined with perfusion flow in vitro for culturing stem cell-derived IPCs.

The Role of MicroRNAs in the Induction of Pancreatic Differentiation

Stem cell-based therapy is one of the therapeutic options with promising results in the treatment of diabetes. Stem cells from various sources are expanded and induced to generate the cells capable of secreting insulin. These insulin-producing cells [IPCs] could be used as an alternative to islets in the treatment of patients with diabetes. Soluble growth factors, small molecules, geneencoding transcription factors, and microRNAs [miRNAs] are commonly used for the induction of stem cell differentiation. MiRNAs are small non-coding RNAs with 21-23 nucleotides that are involved in the regulation of gene expression by targeting multiple mRNA targets. Studies have shown the dynamic expression of miRNAs during pancreatic development and stem cell differentiation. MiR- 7 and miR-375 are the most abundant miRNAs in pancreatic islet cells and play key roles in pancreatic development as well as islet cell functions. Some studies have tried to use these small RNAs for the induction of pancreatic differentiation. This review focuses on the miRNAs used in the induction of stem cells into IPCs and discusses their functions in pancreatic β-cells.

PHBV nanofibers promotes insulin-producing cells differentiation of human induced pluripotent stem cells

Tissue-engineering associated techniques have long been employed to improve the various elements of the therapeutic approaches toward the more efficient ones in diabetic states. The resultant constructs comprise of the polymeric scaffolds with proper degradation rates that produce bodily compatible components, and the pluripotent cells that are highly capable of generating islet-like cells. In this study, Poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibers were fabricated by the Electrospinning. After validation of its 3-D structure, fibers size and non-toxicity, insulin-producing cells (IPC) differentiation potential of the induced pluripotent stem cells (iPSCs) were evaluated during growing on the PHBV nanofibers in comparison with tissue culture polystyrene (TCPS). SEM analyses confirmed the 3-D and nanofibrous structure of the fabricated scaffold. The survival rate of the iPSCs cultured on the PHBV nanofibers was increased significantly compared to the cells cultured on the TCPS, which is an evidence for the non-toxicity of the nanofibers. Insulin and C-peptide secretion levels significantly increased in the differentiated iPSCs on PHBV nanofibers compared to those cells cultured on TCPS. Moreover, levels of the gene transcription and translation results revealed that insulin, Glut-2, and Pdx-1 genes and insulin protein, in IPC-differentiated iPSCs grown on PHBV nanofibers are significantly higher than those cells grown on TCPS. Taken together, these results go beyond previous reports, showing thatiPSCs-PHBV as a promising cell-copolymer construct, could potentially be applied in the pancreatic tissue engineering applications to diabetic patient treatment.

Drug-Induced Naïve iPS Cells Exhibit Better Performance than Primed iPS Cells with Respect to the Ability to Differentiate into Pancreatic β-Cell Lineage

Pluripotent stem cells are classified as naïve and primed cells, based on their in vitro growth characteristics and potential to differentiate into various types of cells. Human-induced pluripotent stem cells (iPSCs, also known as epiblast stem cells [EpiSCs]) have limited capacity to differentiate and are slightly more differentiated than naïve stem cells (NSCs). Although there are several in vitro protocols that allow iPSCs to differentiate into pancreatic lineage, data concerning generation of β-cells from these iPSCs are limited. Based on the pluripotentiality of NSCs, it was hypothesized that NSCs can differentiate into pancreatic β-cells when placed under an appropriate differentiation induction condition. We examined whether NSCs can be efficiently induced to form potentially pancreatic β cells after being subjected to an in vitro protocol. Several colonies resembling in vitro-produced β-cell foci, with β-cell-specific marker expression, were observed when NSC-derived embryoid bodies (EBs) were induced to differentiate into β-cell lineage. Conversely, EpiSC-derived EBs failed to form such foci in vitro. Intrapancreatic grafting of the in vitro-formed β-cell foci into nude mice (BALB/c-nu/nu) generated a cell mass containing insulin-producing cells (IPCs), without noticeable tumorigenesis. These NSCs can be used as a promising resource for curing type 1 diabetes.

Aloe Vera-Derived Gel-Blended PHBV Nanofibrous Scaffold for Bone Tissue Engineering

Today, composite scaffolds fabricated by natural and synthetic polymers have attracted a lot of attention among researchers in the field of tissue engineering, and given their combined properties that can play a very useful role in repairing damaged tissues. In the current study, aloe vera-derived gel-blended poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibrous scaffold was fabricated by electrospinning, and then, PHBV and PHBV gel fabricated scaffolds characterized by scanning electron microscope, protein adsorption, cell attachment, tensile and cell's viability tests. After that, osteogenic supportive property of the scaffolds was studied by culturing of human-induced pluripotent stem cells on the scaffolds under osteogenic medium and evaluating of the common bone-related markers. The results showed that biocompatibility of the PHBV nanofibrous scaffold significantly improved when combined with the aloe vera gel. In addition, higher amounts of alkaline phosphatase activity, mineralization, and bone-related gene and protein expression were detected in stem cells when grown on PHBV-gel scaffold in comparison with those stem cells grown on the PHBV and culture plate. Taken together, it can be concluded that aloe vera gel-blended PHBV scaffold has a great promising osteoinductive potential that can be used as a suitable bioimplant for bone tissue engineering applications to accelerate bone regeneration and also degraded completely along with tissue regeneration.

Insulin production from hiPSC-derived pancreatic cells in a novel wicking matrix bioreactor

Clinical use of pancreatic β islets for regenerative medicine applications requires mass production of functional cells. Current technologies are insufficient for large-scale production in a cost-efficient manner. Here, we evaluate advantages of a porous cellulose scaffold and demonstrate scale-up to a wicking matrix bioreactor as a platform for culture of human endocrine cells. Scaffold modifications were evaluated in a multiwell platform to find the optimum surface condition for pancreatic cell expansion followed by bioreactor culture to confirm suitability. Preceding scale-up, cell morphology, viability, and proliferation of primary pancreatic cells were evaluated. Two optimal surface modifications were chosen and evaluated further for insulin secretion, cell morphology, and viable cell density for human-induced pluripotent stem cell-derived pancreatic cells at different stages of differentiation. Scale-up was accomplished with uncoated, amine-modified cellulose in a miniature bioreactor, and insulin secretion and cell metabolic profiles were determined for 13 days. We achieved 10-fold cell expansion in the bioreactor along with a significant increase in insulin secretion compared with cultures on tissue culture plastic. Our findings define a new method for expansion of pancreatic cells a on wicking matrix cellulose platform to advance cell therapy biomanufacturing for diabetes.

An Overview on Stem Cells in Tissue Regeneration

BACKGROUND

Deteriorations in tissues and decline in organ functions, due to chronic diseases or with advancing age or sometimes due to infections or injuries, can severely compromise the quality of life of an individual. Regenerative medicine, a field of medical research focuses on replacing non-functional or dead cells or repairing or regenerating tissues and organs to restore normal functions of an impaired organ. Approaches used in regenerative therapy for achieving the objective employ a number of means which include soluble biomolecules, stem cell transplants, tissue engineering, gene therapy and reprogramming of cells according to target tissue types. Stem cells transplant and tissue regeneration methods for treating various diseases have rapidly grown in usage over the past decades or so. There are different types of stem cells such as mesenchymal, hematopoietic, embryonic, mammary, intestinal, endothelial, neural, olfactory, neural crest, testicular and induced pluripotent stem cells.

METHODS

This review covers the recent advances in tissue regeneration and highlights the application of stem cell transplants in treating many life-threatening diseases or in improving quality of life.

RESULTS

Remarkable progress in stem cell research has established that the cell-based therapy could be an option for treating diseases which could not be cured by conventional medical means till recent. Stem cells play major roles in regenerative medicine with its exceptional characteristics of self-renewal capacity and potential to differentiate into almost all types of cells of a body.

CONCLUSION

Vast number of reports on preclinical and clinical application of stem cells revealed its vital role in disease management and many pharmacological industries around the globe working to achieve effective stem cell based products.

microRNA expression profiles in two- and three-dimensional culture conditions of human-umbilical-cord blood-derived CD34+ cells

Human umbilical cord blood (HUCB) is a suitable source of hematopoietic stem cells (HSCs) for therapeutic transplantation. Different approaches have been used to expand the number of HSCs to increase the rate of HSC transplantation success in patients, such as using different cocktails of cytokines, feeder cell layers, and biocompatible scaffolds. microRNAs (miRNAs) are small noncoding RNAs that regulate gene expression posttranscriptionally. They play crucial roles in hematopoiesis including stem cell proliferation, differentiation, stemness, and self-renewal properties. Here, we studied the UCB-derived CD34⁺ cell expansion and the miRNA signatures of CD34⁺ cells on two- and three-dimensional (2D and 3D) culture conditions. We successfully expanded the UCB-derived CD34⁺ cells in both liquid culture (2D) and on aminated polyethersulfone nanofiber scaffolds (3D). Next, we identified the miRNA signature of CD34⁺ cells and their target genes. We found 58 dysregulated miRNAs in 3D culture condition and 34 dysregulated miRNAs in 2D culture condition when compared to the freshly isolated CD34⁺ cells. Various types of target genes were also predicted in both conditions using two online databases.

Generation of Human Stem Cell-Derived Pancreatic Organoids (POs) for Regenerative Medicine

Insulin-dependent diabetes mellitus or type 1 diabetes mellitus (T1DM) is an auto-immune condition characterized by the loss of pancreatic β-cells. The curative approach for highly selected patients is the pancreas or the pancreatic islet transplantation. Nevertheless, these options are limited by a growing shortage of donor organs and by the requirement of immunosuppression.Xenotransplantation of porcine islets has been extensively investigated. Nevertheless, the strong xenoimmunity and the risk of transmission of porcine endogenous retroviruses, have limited their application in clinic. Generation of β-like cells from stem cells is one of the most promising strategies in regenerative medicine. Embryonic, and more recently, adult stem cells are currently the most promising cell sources exploited to generate functional β-cells in vitro. A number of studies demonstrated that stem cells could generate functional pancreatic organoids (POs), able to restore normoglycemia when implanted in different preclinical diabetic models. Nevertheless, a gradual loss of function and cell dead are commonly detected when POs are transplanted in immunocompetent animals. So far, the main issue to be solved is the post-transplanted islet loss, due to the host immune attack. To avoid this hurdle, nanotechnology has provided a number of polymers currently under investigation for islet micro and macro-encapsulation. These new approaches, besides conferring PO immune protection, are able to supply oxygen and nutrients and to preserve PO morphology and long-term viability.Herein, we summarize the current knowledge on bioengineered POs and the stem cell differentiation platforms. We also discuss the in vitro strategies used to generate functional POs, and the protocols currently used to confer immune-protection against the host immune attack (micro- and macro-encapsulation). In addition, the most relevant ongoing clinical trials, and the most relevant hurdles met to move towards clinical application are revised.

The emerging field of pancreatic tissue engineering: A systematic review and evidence map of scaffold materials and scaffolding techniques for insulin-secreting cells

A bioartificial endocrine pancreas is proposed as a future alternative to current treatment options. Patients with insulin-secretion deficiency might benefit. This is the first systematic review that provides an overview of scaffold materials and techniques for insulin-secreting cells or cells to be differentiated into insulin-secreting cells. An electronic literature survey was conducted in PubMed/MEDLINE and Web of Science, limited to the past 10 years. A total of 197 articles investigating 60 different materials met the inclusion criteria. The extracted data on materials, cell types, study design, and transplantation sites were plotted into two evidence gap maps. Integral parts of the tissue engineering network such as fabrication technique, extracellular matrix, vascularization, immunoprotection, suitable transplantation sites, and the use of stem cells are highlighted. This systematic review provides an evidence-based structure for future studies. Accumulating evidence shows that scaffold-based tissue engineering can enhance the viability and function or differentiation of insulin-secreting cells both in vitro and in vivo.

Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) improved osteogenic differentiation of the human induced pluripotent stem cells while considered as an artificial extracellular matrix

Cocell polymers can be the best implants for replacing bone defects in patients. The pluripotent stem cells produced from the patient and the nanofibrous polymeric scaffold that can be completely degraded in the body and its produced monomers could be also usable are the best options for this implant. In this study, electrospun poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibers were fabricated and characterized and then osteogenic differentiation of the human-induced pluripotent stem cells (iPSCs) was investigated while cultured on PHBV scaffold. MTT results showed that cultured iPSCs on PHBV proliferation were increased compared to those cultured on tissue culture polystyrene (TCPS) as the control. Alkaline phosphatase (ALP) activity and calcium content were also significantly increased in iPSCs cultured on PHBV compared to the cultured on TCPS under osteogenic medium. Gene expression evaluation demonstrated that Runx2, collagen type I, ALP, osteonectin, and osteocalcin were upregulated in iPSCs cultured on PHBV scaffold in comparison with those cultured on TCPS for 2 weeks. Western blot analysis have shown that osteocalcin and osteopontin expression as two major osteogenic markers were increased in iPSCs cultured on PHBV scaffold. According to the results, nanofiber-based PHBV has a promising potential to increase osteogenic differentiation of the stem cells and iPSCs-PHBV as a cell-co-polymer construct demonstrated that has a great efficiency for use as a bone tissue engineered bioimplant.